Blocked Missions

As you play through the main story, some side missions can be blocked. To check which ones they are, go to your missions list and sort it by type. The missions in question will be listed under the "Blocked" category.

A blocked mission cannot be selected from the missions list, can not be started or, if already completed (and listed as green) cannot be turned in. This happens with missions where the characters or locations play a role in the main quest and are inaccessible at the time.

To complete blocked side quests, simply keep on progressing through the main quest. Some quests may be temporarily blocked when Sanctuary is inaccessible and can be accessed again once you finish the related events. Others, related to Lilith, for example are blocked later in the game. Once you finish the final mission, all blocked quests are unblocked and you can complete them just fine.

Alternatively, you can play co-op with another player who has not progressed through the story as far and complete the mission on his save (which will count towards your mission progression).